The Internet Storm Center says port 2 TCP is becoming popular. I’m also seeing scans to port 57 TCP, which has history dating to Oct 02 and Nov 02. This is a signature of a tool called FX-Scanner (analysis) Apparently port 57 is used as a host discovery mechanism. This has only picked up in the last few days. It appears to be associated with the Backdoor.OptixPro tool BackdooroptPro. BackdoorOptix Pro appears to have scanned ports 1433 and 445.”]
Source: https://taosecurity.blogspot.com/2003/06/checking-my-argus-logs-this-morning-i.html